laptop AC adapter tolerances

I've used a 90 watt 20 volt adapter on a laptop which requires 19 volts at 55 watts for maybe 2 years now with no apparent damage. 1 volt isn't likely to be an issue and the laptop will not consume more power than it needs.

Thanks for that, I wasnt sure: I knew that the 6A wouldn't be a problem as the unit doesn't consume any more amps than it needs but didnt know that if it only needed 19v, the adapter wouldnt just keep on pumping 20v into it

Regulation on a lot of supplies is within a volt anyway. Unless the charging/distribution electronics of the laptop are poorly designed I wouldn't anticipate one extra volt being any problem. I've been using an HP 20 volt supply on a Toshiba that ran on 19 and like I said no problems after a couple years. I'm also using a 19 volt Dell supply on an Asus that takes 19 volts. However when measured the 19 volt supply outputted almost 20 volts. There are no + - tolerance specs printed on the side of the supply. If it were plus or minus 5 % that would be pretty close to one volt either way on 19 volt output.

A tolerance of at least 10% would be reasonable, so 19.0 + 1.9 =3D 19.9 which is almost 20V. 20V - 2.0 V =3D 18V for the minimum on the 20V supply, so you should be just fine.

That was 20.9, when I went to school ... ;-)

Arfa

New math.

PlainBill

Actually I see the maths differently, though given the responses which say that it is OK and has been shown to be OK over a few-year period, the result is the same: If a laptop takes 19 volts, can I use a converter over a prolonged period which could put out a continuous 22 volts?